Maternal gestational weight gain (GWG) and rapid infant weight gain are important determinants of a child's lifelong risk of obesity. It is particulrly important to improve these outcomes in the Latino population, where rates of obesity and its associated comorbidities are higher than in the general population. The proposed study (GROW Baby) will test how a behavioral intervention supports healthy maternal GWG (Aim 1) and healthy infant growth (Aim 2). By developing a nested sub-cohort from an ongoing randomized healthy lifestyle trial known as Growing Right Onto Wellness (GROW), GROW Baby will collect new data from both Latina women who become pregnant and their infants born during the study. GROW is a culturally tailored intervention that teaches healthy nutrition and physical activity for both mother and pre-school child (aged 3-5 years). The control condition is a school readiness program. Because intervention-group mothers who become pregnant during the study learn these healthy lifestyle skills prior to or early in pregnancy, the intervention has the potential to support healthy maternal GWG and future infant growth. A committed primary mentor and a multidisciplinary team of co-mentors will oversee the candidate's progression to becoming an independently funded physician scientist with a focus on leveraging healthy behavior changes during pregnancy to prevent and treat maternal and child obesity. The career development plan integrates advanced training in behavioral interventions, community engagement methods, the maternal- child interaction, and targeted approaches to underserved populations. The candidate will gain exposure to senior mentors with expertise in behavioral trials and perinatal nutrition, and will participate in 1) advanced coursework; 2) an ongoing intervention to prevent pediatric obesity; 3) community engagement activities; and 4) a multi-pronged approach applying cultural sensitivity skills to community research with Latino populations. In conducting the proposed research, the candidate will advance the field of maternal-child obesity prevention by understanding how a behavioral intervention implemented before and during pregnancy could support healthy weight for both mother and child.